Lower margin indicator for typewriters



April 21, 1942.. F. F. DRABIC K 2,280,145

- LOWER. MARGIN INDICATOR FOR 'IYPEWRITERS,

Filed octQz, 195s Y v INVENTOR.

' y 5259 FZDRABICK T ORNEYS.

the foot of a sheet Patented Apr. 21, 1942 UNITED} STATES PATENT OFFICE LOWER MARGIN INDICATOR FOR TYPEWRITERS Fred F. Drabick, Seattle, Wasln, assignor of onethird to George E. Bradner and one-third to Herbert 0. Landon, both of Seattle, Wash.

Application October 2, 1939, Serial No. 297,574

3 Claims.

This invention relates to typewriters, and particularly to attachments thereto for indicating when a predetermined clear margin remains at,

mining when a desired position has been reached is required and, in order to give such attention, the mind of the operator is.diverted from his writings.

It is therefore an object of this invention to provide a simple and inexpensive device as a part of a typewriter or as an attachment thereto,

whereby a signal will be automatically given or the platen stopped when the paper in the typewith means operably connected to said disc to give a signal, or stop, for the margin when a predetermined position on the paper over the platen has been reached.

A particular'object is to provide a series of dial numerals around the periphery of the disc, calibrated to indicate the number of inches or other predetermined divisions around the cirior the purpose of illustrating the use of my device and convenience and understanding thereof. With these and other objects to be hereinafter stated, I have illustratively exemplified my invention by the accompanying drawing of which: 'Figure 1 is a perspective view of the device with parts broken away.

Figure 2 is a front elevation of the device with a portion of a platen.

. Figure 3 is an end elevation ofthe device with parts broken away and showing portions of the disc or crown gear and pinion, with the stop latch and electrical connections for the signal.

Figure 4 is a detail front edge view of the disc,

or crown gear, and dial numerals disposed around the periphery thereof.

Figure 4% is a detail obverse edge view of the crown gear, showing the stop notch for the latch. Figure 5 shows a fragmentary vertical view of an alternate plan for creating a sound signal by operation of the latch lever.

Figure 6 shows a fragmentary detail view of a third form, with a portion of the device, operated by a latch lever with a point, for stopping the rotation of the platen when a predetermined position on the disc has been reached thereby.

Like numerals on the different figures represent like parts. Ill represents the right-hand end of any typewriter platen,'with an ordinary shaft I I, and handle knob I2; l3 represents teeth on a pinion l3 which is affixed to the shaft as by set screw ll. i5 represents the housing adapted to be attached to the carriage frame it of a typewriter as by screw II. A disc in the form of a crown gear I8, is rotatably mounted on an axle is, which is disposed through the ,housing. Teeth 20 of the gear or disc mesh with the teeth ll of the pinion through a slot 22 in the wall of the housing. The pinion is relatively cumference of the platen, the position of such numerals on the dial to depend on the ratio of the disc gear and the pinion, and also on the respective circumference of the platen and the disc, and the said numerals to serve for the purpose of determining the points for the setting of the disc to provide the desired margin to be left on the respective sheet of paper.

While the device may be adapted to be used for any length of paper, I have in this case prepared the description to cover specifically the use thereof for legal sized paper 13 inches in length,

small, in order that it shall turn with the platen a greater distance or for more revolutions than the gear will turn during the same time. Around upon the periphery of the disc, are disposed a series of dial numerals 2|, as guides for setting the gear or disc for use when writing upon a predetermined length of paper for a predetermined number of lines to leave the desired margin at the end; said numerals are arranged in calibrated relation with the number of inches around the circumference of the given platen and also with the circumference of the disc, and also with the ratio of the gear and the pinion. In the drawing such numerals are shown in series from I to l3 as intended for use on a sheet of paper not exceeding 13 inches in length.

At one point on the periphery of the disc is located anotch 23, which may be an extension of one of the spaces between the teeth of the gear. An aperture 24 is provided in the front of the housing for use in sighting therethrough for setting the respective numerals in predetermined position withrelation to the notch and platen, in order to provide a stop, or signal, when the paper has traveled the desired distance over the platen to leave the width of margin desired. In Fig. 3, arrangements are shown for making a signal at the predetermined position of IS.

Numeral 25 represents a lever or a latch bar which is pivotally mounted over a pintle 2S, supported through the housing. One end, 21, of the lever is curved in U formation and the base of the curve is resiliently depressed against the periphery of the disc by spring 28, projected below the housing. The opposite end of the lever is angularly extended as 29, for contacting a light socket and contact plate 30, for closing an electrical circuit for an ordinary lamp II, to be lighted by an ordinary battery 32. The battery is connected with a supporting frame 84 at the lower end thereof by spring 33, and to be connected with the frame at the upper end of the battery by the closing of the circuit as above described by the latch lever. represents ordinary electrical insulation from the supporting frame.

In Fig. 3, the U is shown depressed in the notch and the circuit so closed by the end 29, in contact with the plate 30. to illumine the lamp. When the gear is next moved in either direction, the U is raised thereby and the end of the bar 29 so separated from the pole plate and the light ceases.

In operation, when a sheet of paper is to be inserted over the platen, theoperator first determines the number of inches of margin desired to be left clear at the bottom of the sheet or the number of inches to be printed on the sheet above the margin. As for illustration, if he wishes a one-inch margin to remain on a 13 inch length of paper, he turns the gear until the numeral l2 thereon appears beneath said aperture. Then, as the platen is turned in the writing operation, the gear is slowly revolved until 12 inches have been covered and said notch will have reached a position beneath the U of the latch, thereby causing a signal or stop with one inch left for margin on a sheet of paper.

If he should prefer a two-inch margin on a sheet of paper, he turns the gear until the numeral ll appears beneath said aperture and th signal will then be given when the writing has reached a point two inches above the lower ing element, as II indicated in Fig. 5, may be positioned in lieu of the plate 30, to be struck by the end of bar 29 for sounding an alarm when the opposite end or the U member has dropped into the notch.

In some instances it may be preferable to have the platen and disc brought to a stop or locked when the notch is met by the latch. This may be accomplished by providing in lieu of the U bend, a latch point 38, as shown in Fig. 6, on the bar, bent downwardly at right angles thereto and adapted to drop into the notch and thereby prevent further forward movement of the disc and platen. This point 35 has a bevel 31 on the front edge thereof adapted to ride over the side of the notch and to permit the disc and platen to be turned backwardly by the operator for resetting the device or for the insertion of a new sheet of pa e For manually raising the point 36 from the notch, and to retain the same so raised, a pawl 39, may be mounted on a pivot 40, from the housing top It, with the lower end of the pawl slidably disposed on the rear end of the latch arm. Normally the pawl is obliquely disposed, but a handle ll, on the upper end thereof, enables the operator to move the pawl into perpendicular position, whereby the arm is depressed and the latch point raised.

From the foregoing description it will be understood that the dial numerals are calibrated to indicate the inches or other determined spaces around the circumference of the platen, that the positioning of the dial numbers depends on the ratio of the gear and pinion, and also on the circumference of any given platen and disc, and that the location of the highest numeral on the dial is at such a point that it will show through the aperture when the latch is in the notch. In practice, the dial is first turned until the numeral representing the last inch of line of desired travel is beneath the aperture, and the paper is then inserted and the typewriter operated in the usual manner, until the last described numeral again reaches the notch when the signal. will be given.

While I have shown and described particular embodiments of my invention, I do not wish to limit myself to the exact forms shown, since the particular constructions shown and described are intended as illustrative rather than delimitive of the invention. The principle underlying my invention can be applied to various makes of typewriters with minor changes in the construction of the parts hereinabove referred to, but not specifically described, illustrated or referred to, as it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention orfrom the scope of the appended claims.

Having thus described my invention, what I ent is:

1. An attachment for a typewriter for determining a clear margin to be left on the lower edge of a sheet of paper, comprising an electrical circuit and signal in combination with a crown gear rotatably supported on one end of the carriage, a pinion afllxed to the platen shaft for rotating the gear, a stopping notch on the periphery of the gear, an arm pivotally mounted over the gear, with one end thereof slidably disposed on said periphery and adapted to contact said notch to close said circuit and cause operation of the signal when said contact is made, the ratio between said gear and pinion being such that said gear makes one revolution while the platen makes more than one revolution, a series of dial numerals disposed around the periphery of the gear, and calibrated in relation to the number of inches around the platen and the circumference of the gear and with relation to the ratio between said pinion and Bear, said dial numerals adapted to be severally selected for setting the positions of the gear to cause operation of the signal when the gear has been rotated a distance corresponding with the numeral selected.

2. A typewriter attachment, comprising electrical contact points normally separated while said typewriter is operated, a control disc operably connected with the platen to be rotated thereby and having a notch in the periphery thereof, a

rotation of said disc to close said circuit and cause the signal to begiven.

3. A typewriter attachment, comprising a control disc rotatably disposed adjacent the platen and operably rotated by the shaft of the platen in the ratio of one turn of the disc to a predetermined greater distance of travel or number of turns of the platen, said discprovided with a notch in the periphery thereof, a pair of normally separated electrical contact points, a Sig naling lamp in circuit with said contact points,

and a pivoted lever comprising one of said points and having one end thereof resiliently and slidably disposed normally on the periphery of said disc and adapted to enter said notch when the same has been moved to a predetermined position, and the other end thereof adapted to close said circuit and cause a light to shine when said notch is so entered.

FRED F. DRABICK. 

